Reduced pressure wound treatment system

ABSTRACT

A reduced pressure treatment appliance is provided for treating a wound on the body of a patient. In some embodiments, the appliance comprises a cover, which can have a top cup member and an interface member. The interface member can have flow control means, configured to permit exudate from the wound to flow through the flow control means into the volume under the cover, but not in the opposite direction. Also, in some embodiments, the top cup member can have a lid member, a cup body member, and lid attachment means to removably attach the lid member to the cup body member. In some embodiments, the cover can be configured to facilitate access to the wound for monitoring, treatment and other purposes without removing the cover from the body. The wound treatment appliance can have a vacuum system to supply reduced pressure to the site of the wound in the volume under the cover. A suction bulb can he used lo provide a source of reduced pressure to the cover. Additionally, methods are provided for using various embodiments of the treatment appliance.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.11/098,203, filed on Apr. 4, 2005, which claims the benefit of U.S.Provisional Application No. 60/559,727, filed on Apr. 5, 2004. The fulldisclosures of U.S. application Ser. No. 11/098,203 and U.S. ProvisionalApplication No. 60/559,727 are hereby incorporated by reference as iffully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to treatment of wounds, and morespecifically to improved apparatus and methods for treating a wound on apatient's body by applying reduced pressure to the body at the site ofthe wound. In this context, the term “wound” is to be interpretedbroadly, to include any wound that may be treated using reducedpressure.

2. Description of the Related Art

The treatment of open or chronic wounds that are too large tospontaneously close or otherwise fail to heal by means of applyingreduced pressure to the site of the wound is well known in the art. Onesuch system is disclosed in U.S. patent application Ser. No. 10/652,100,which was filed with the U.S. Patent and Trademark Office on Aug. 28,2003. The disclosure of this U.S. patent application is incorporatedherein by reference. Another system is disclosed in U.S. patentapplication Ser. No. 11/026,733, entitled “Improved Reduced PressureWound Treatment Appliance,” which was filed with the U.S. Patent andTrademark Office on Dec. 30, 2004. The disclosure of this U.S. patentapplication is also incorporated herein by reference. Yet another systemis disclosed in U.S. patent application Ser. No. 11/064,813, entitled“Improved Flexible Reduced Pressure Wound Treatment Appliance,” whichwas filed with the U.S. Patent and Trademark Office on Feb. 24, 2005.The disclosure of this U.S. patent application is also incorporatedherein by reference.

Reduced pressure wound treatment systems currently known in the artcommonly involve placing a treatment device that is impermeable toliquids over the wound, using various means to seal the treatment deviceto the tissue of the patient surrounding the wound, and connecting asource of reduced pressure (such as a vacuum pump) to the treatmentdevice in a manner so that an area of reduced pressure is created underthe treatment device in the area of the wound. The systems alsotypically act to remove exudate that may be aspirated from the wound.Thus, such systems also typically have a separate collection devicelocated between the reduced pressure source and the treatment device tocollect. This collection device represents a separate source of expensein reduced pressure wound treatment. In addition, it is advantageous insome circumstances to remove exudate from the wound so that the exudatedoes not remain in the presence of the wound. For example, healing ofthe wound may be enhanced by the removal of exudate from the wound insome circumstances. In yet other cases, it may be advantageous to beable to gain physical access to the wound without having to remove thetreatment device from the body surrounding the wound. For example, itmay be desirable to monitor or treat the condition of the wound duringthe treatment process. If the treatment device is sealed to the bodyusing an adhesive tape, removing the adhesive tape to monitor or treatthe wound may cause discomfort and pain for the patient.

Therefore, there is a need for a wound treatment device that caneliminate the requirement for a separate collection device to collectexudate from the wound. This type of device could reduce the expenseinvolved in wound treatment by eliminating the need for the collectiondevice. There is also a need for such a treatment device to removeexudate from the presence of the wound to aid in wound healing. It mayalso be desirable for this type of treatment device to be disposable incertain circumstances. Further, there is a need for a treatment devicethat would allow for physical access to the wound without the need forremoving the treatment device from the body. This type of device couldenhance patient comfort. In addition, where the access is simple andquickly obtained, it could also decrease the cost of wound treatment byreducing the time required of healthcare practitioners to be involved inwound treatment. Finally, there is also a need for a reduced pressuretreatment system that is relatively inexpensive, while meeting the needsdescribed above.

SUMMARY OF THE INVENTION

The present invention is directed to reduced pressure treatmentappliances and methods that satisfy the needs described above. Asdescribed in greater detail below, they have many advantages overexisting reduced pressure treatment apparatus and methods when used fortheir intended purpose, as well as novel features that result in newreduced pressure treatment appliances and methods that are notanticipated, rendered obvious, suggested, or even implied by any of theprior art apparatus or methods, either alone or in any combinationthereof.

In accordance with the present invention, a treatment appliance isprovided for treating a wound on a body by applying reduced pressure(i.e., pressure that is below ambient atmospheric pressure) to the woundin a controlled manner for a selected time period in a manner thatovercomes the disadvantages of currently existing apparatus. Forexample, the application of reduced pressure to a wound provides suchbenefits as faster healing, increased formation of granulation tissue,closure of chronic open wounds, reduction of bacterial density withinwounds, inhibition of burn penetration, and enhancement of flap andgraft attachment. Wounds that have exhibited positive response totreatment by the application of negative pressure include infected openwounds, decubitus ulcers, dehisced incisions, partial thickness bums,and various lesions to which flaps or grafts have been attached.

In one embodiment of a first version of the present invention, anappliance for treating a wound on a body is comprised of a cover,sealing means to seal the cover to the body, which are described in moredetail below, and reduced pressure supply means, which are alsodescribed in more detail below. The cover, which is sized to be placedover and enclose the wound, is further comprised of a top cup member, aninterface member, and interface attachment means for removably attachingthe top cup member to the interface member. The interface member isfurther comprised of flow control means that permit exudate from thewound to flow from the wound into the top cup member, but not in theopposite direction. Thus, in this embodiment, the interface member issealed to the body by the sealing means and exudate from the wound flowsfrom the wound through the flow control means in the interface memberinto the volume of the cover above the interface member. The flowcontrol means do not allow the exudate to flow back into the area of thewound under the interface member. The cover and the sealing means allowreduced pressure to be maintained in the volume under the cover at thesite of the wound. The reduced pressure supply means operably connectthe cover to a reduced pressure supply source that provides a supply ofreduced pressure to the cover, so that the volume under the cover at thesite of the wound is supplied with reduced pressure by the reducedpressure supply source.

In some embodiments of this first version of the present invention, thecover may be approximately cylindrical in shape. In other embodiments,the cover may be approximately cup-shaped. In some embodiments, thesealing means may be comprised of the suction of the interface memberagainst the body, such suction being produced by the presence of reducedpressure in the volume under the cover at the site of the wound. Instill other embodiments, the top cup member and the interface member areeach comprised of materials from the group consisting of semi-rigidmaterials, rigid materials, and combinations of such materials. Further,in some embodiments, the interface member is further comprised of amembrane portion that is disposed approximately adjacent to the body andthe flow control means is comprised of at least one one-way valveoperably disposed in the membrane portion. In other embodiments, theinterface member may be further comprised of a membrane portion that isdisposed approximately adjacent to the body and that permits fluid toflow in only one direction, and the flow control means is comprised ofall or a portion of the membrane. In some embodiments of this firstversion of the present invention, the interface attachment means may becomprised of an o-ring seal or a magnetic seal. In other embodiments, aportion of the interface member may be of a size and shape adapted tofit tightly against a portion of the top cup member, wherein an operableseal (described in more detail below) is created between the interfacemember and the top cup member. In yet other embodiments, the sealingmeans may be comprised of an adhesive that is disposed between a portionof the cover and the portion of the body adjacent to said portion of thecover. In still other embodiments, the sealing means may be comprised ofan adhesive tape that is disposed over a portion of the cover and theportion of the body adjacent to said portion of the cover. In otherembodiments, the top cup member is further comprised of a port and flowshutoff means operably connected to the port, wherein the flow shutoffmeans halt or inhibit the supply of reduced pressure to the cover whenthe level of exudate under the cover at the site of the wound reaches apredetermined level. In yet other embodiments, the interface attachmentmeans does not provide for removal of the top cup member from theinterface member.

In some embodiments of this first version of the present invention, thetop cup member of the cover may be further comprised of a lid member, acup body member, and lid attachment means to removably attach the lidmember to the cup body member. In some of these embodiments, the coveris approximately cylindrical in shape. In other embodiments, theinterface attachment means provides for removable attachment of the topcup member to the interface member, but does not provide for permanentattachment of the top cup member to the interface member. In some ofthese embodiments, the interface attachment means may be comprised of ano-ring seal or a magnetic seal. In other embodiments, a portion of theinterface member may be of a size and shape adapted to fit tightlyagainst a portion of the top cup member, wherein an operable seal iscreated between the interface member and the top cup member. In stillother embodiments, the interface attachment means provides for permanentattachment of the top cup member to the interface member, but does notprovide for removable attachment of the top cup member to the interfacemember. In yet other embodiments, the lid attachment means may becomprised of an o-ring seal or a magnetic seal. In other embodiments, aportion of the lid member is of a size and shape adapted to fit tightlyagainst a portion of the cup body member, wherein an operable seal iscreated between the lid member and the cup body member.

In other embodiments of this first version of the present invention, thecover is comprised of a lid member, a cup body member, and lidattachment means to removably attach the lid member to the cup bodymember. In these embodiments, the cover is sized to be placed over andenclose the wound and adapted to maintain reduced pressure in the volumeunder the cover at the site of the wound. Also in these embodiments, thesealing means, which are described in more detail below, are used toseal the cup body member of the cover to the body so that reducedpressure may be maintained in the volume under the cover at the site ofthe wound. Reduced pressure supply means operably connect the cover to areduced pressure supply source, which provides a supply of reducedpressure to the cover so that the volume under the cover at the site ofthe wound is supplied with reduced pressure by the reduced pressuresupply source. In some of these embodiments, the lid attachment meansmay be comprised of an o-ring seal or a magnetic seal. In otherembodiments, a portion of the lid member is of a size and shape adaptedto fit tightly against a portion of the cup body member, wherein anoperable seal is created between the lid member and the cup body member.In some of these embodiments, a portion of the lid member isapproximately cylindrical in shape and a portion of the cup body memberis approximately cylindrical in shape and said portions have threads andmeans to receive threads, so that when such portions are screwedtogether an operable seal is created between the lid member and the cupbody member.

In a second version of the present invention, an appliance foradministering reduced pressure treatment to a wound on a body iscomprised of a treatment device and a vacuum system. In variousembodiments of this second version of the invention, the treatmentdevice is also comprised of a cover and sealing means, which may havesubstantially the same structure, features, characteristics andoperation as the cover and sealing means, respectively, described abovein connection with the first version of the present invention. In thissecond version of the invention, the vacuum system is further comprisedof a reduced pressure supply source that provides a supply of reducedpressure and reduced pressure supply means (which are described in moredetail below) to operably connect the treatment device to the reducedpressure supply source, so that the volume under the treatment device atthe site of the wound is supplied with reduced pressure by the reducedpressure supply source. In various embodiments of this second version ofthe invention, the reduced pressure supply means may generally havesubstantially the same structure, features, characteristics andoperation as the reduced pressure supply means described above inconnection with the first version of the invention.

In some embodiments of this second version of the invention, the reducedpressure supply source is comprised of a vacuum pump. In some of theseembodiments, the reduced pressure supply source further comprises acontrol system for the vacuum pump, wherein the control system maycontrol at least the level of suction produced by the vacuum pump or therate of fluid flow produced by the vacuum pump, or any combination ofrate of suction and rate of fluid flow of the vacuum pump. In otherembodiments, the reduced pressure supply source further comprises afilter operably positioned between the vacuum pump and the reducedpressure supply means. In these embodiments, the filter prevents theventing of and contamination of the vacuum pump by micro-organisms orfluids (or both) aspirated from the wound. In yet other embodiments, thevacuum pump is comprised of a portable vacuum pump. In still otherembodiments of this second version of the invention, the reducedpressure supply means is comprised of flexible tubing. In otherembodiments, the cover is further comprised of a port and flow shutoffmeans, wherein the flow shutoff means halts or inhibits the applicationof reduced pressure to the cover when exudate from the wound reaches apredetermined level within the cover. In yet other embodiments of thissecond version of the invention, the reduced pressure under the cover atthe site of the wound is in the range from approximately 20 mm of Hgbelow atmospheric pressure to approximately 125 mm of Hg belowatmospheric pressure. In other embodiments, the reduced pressure isapplied in a cyclic nature, the cyclic nature providing alternating timeperiods of application of reduced pressure and without application ofreduced pressure.

In a third version of the present invention, an appliance foradministering reduced pressure treatment to a wound on a body iscomprised of a treatment device and a vacuum system. In variousembodiments of this third version of the invention, the treatment deviceis also comprised of a cover and sealing means, which may havesubstantially the same structure, features, characteristics andoperation as the cover and sealing means, respectively, described abovein connection with the first and second versions of the presentinvention. In the various embodiments of this third version of theinvention, the vacuum system is comprised of a suction bulb, which may(but not necessarily) provide a source of reduced pressure, and reducedpressure supply means, which are described in more detail below, tooperably connect the cover to the suction bulb, so that the site of thewound in the volume under the cover may be supplied with reducedpressure by the suction bulb. In some embodiments of this third versionof the invention, the suction bulb is further comprised of an inlet portand an outlet port, wherein the inlet port is operably connected to thereduced pressure supply means, and the vacuum system further comprisesan exhaust tubing member operably connected to the outlet port. In someof these embodiments, the vacuum system further comprises an exhaustcontrol valve operably connected to the exhaust tubing member. In otherembodiments, the vacuum system is further comprised of a filter operablyconnected to the exhaust tubing member, which prevents the venting ofmicro-organisms or fluids (or both) aspirated from the wound. In yetother embodiments, the vacuum system is further comprised of asupplemental vacuum system that is operably connected to the exhausttubing member. In these embodiments, the supplemental vacuum system maygenerally have substantially the same structure, features,characteristics and operation as the vacuum system described above inconnection with the second version of the invention.

A fourth version of the present invention discloses a method of treatinga wound. In one embodiment of this fourth version of the invention, themethod comprises the following steps. First, a cover is positioned onthe body over the wound, wherein the cover may have substantially thesame structure, features, characteristics and operation as theembodiments of the cover described above in connection with the first,second and third versions of the invention. Second, the cover isoperably sealed to the body so that reduced pressure may be maintainedin the volume under the cover at the site of the wound. Third, the coveris operably connected with a vacuum system for producing reducedpressure in the volume under the cover at the site of the wound. Fourth,the reduced pressure is maintained until the wound has progressed towarda selected stage of healing. In other embodiments of this fourth versionof the invention, the vacuum system is comprised of a suction bulb andthe method further comprises the step of squeezing the suction bulb toreduce its volume and then releasing the suction bulb, so that reducedpressure is produced in the volume under the cover at the site of thewound. In other embodiments of this fourth version of the invention, thereduced pressure under the cover at the site of the wound is in therange from approximately 20 mm of Hg below atmospheric pressure toapproximately 125 mm of Hg below atmospheric pressure. In still otherembodiments of this fifth version of the invention, the reduced pressureis applied in a cyclic nature, the cyclic nature providing alternatingtime periods of application of reduced pressure and without applicationof reduced pressure. In other embodiments, the cover is furthercomprised of a lid member, a cup body member, and lid attachment meansto removably attach the lid member to the cup body member, and themethod further comprises the steps of halting the application of reducedpressure to the cover, removing the lid member from the cup body member,and attending to the wound. In some of these embodiments, the methodfurther comprises the steps of re-attaching the lid member to the cupbody member after attending to the wound and then reapplying reducedpressure to the volume under the cover in the area of the wound. Instill other embodiments of this fourth version of the invention, the topcup member further comprises a port and flow shutoff means operablyconnected to the port, wherein the flow shutoff means halts or hindersthe supply of reduced pressure to the volume under the cover in the areaof the wound when the level of exudate within the cover reaches apredetermined level. In these embodiments, the method may furthercomprise the steps of monitoring the level of exudate aspirated from thewound that accumulates within the volume of the cover and removing thecover from the body when the level of exudate aspirated from the woundcauses the flow shutoff means to halt or hinder the supply of reducedpressure to the volume under the cover in the area of the wound. It isto be noted that in various other embodiments the steps described abovemay be performed in a different order than that presented.

The present invention therefore meets the needs discussed above in theBackground section. For example, some embodiments of the presentinvention can eliminate the requirement for a separate collection deviceto collect exudate from the wound because the exudate is collected andretained within the volume under the cover. In these embodiments, theinterface member is sealed to the body by the sealing means and exudatefrom the wound flows from the wound through the flow control means inthe interface member into the volume of the cover above the interfacemember. The flow control means do not allow the exudate to flow backinto the area of the wound under the interface member. Thus, this typeof device could reduce the expense involved in wound treatment byeliminating the need for the collection device. This treatment devicealso removes exudate from the presence of the wound to aid in woundhealing. It is also possible for this type of treatment device to bedisposable. Further, some embodiments of the treatment device allow forphysical access to the wound without the need for removing the treatmentdevice from the body. In these embodiments, the lid member may beremoved from the cup body member of the cover, exposing the area of thewound if an interface member is not utilized. This embodiment of thedevice could enhance patient comfort because it would not be necessaryto remove the sealing means to access the wound. In addition, becauseaccess is simple and quickly obtained, the present invention may alsodecrease the cost of wound treatment by reducing the time required ofhealthcare practitioners to be involved in wound treatment. The presentinvention should also be relatively inexpensive to produce, whilemeeting the needs described above. Finally, as can be observed from theforegoing discussion, the present invention has great flexibility. Invarious embodiments, it may be used with or without the interfacemember, as well as with or without the removable lid feature.

There has thus been outlined, rather broadly, the more primary featuresof the present invention. There are additional features that are alsoincluded in the various embodiments of the invention that are describedhereinafter and that form the subject matter of the claims appendedhereto. In this respect, it is to be understood that the invention isnot limited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the following drawings. This invention may be embodied inthe form illustrated in the accompanying drawings, but the drawings areillustrative only and changes may be made in the specific constructionillustrated and described within the scope of the appended claims. Theinvention is capable of other embodiments and of being practiced andcarried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein are for the purpose of thedescription and should not be regarded as limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofthe preferred embodiments of the present invention, will be betterunderstood when read in conjunction with the appended drawings, inwhich:

FIG. 1 is an exploded perspective view of an embodiment of a covercomprising the present invention, as such cover would appear from abovethe body of a patient while the cover is positioned on the body;

FIG. 2A is an plan view of the interface member of the embodiment of thecover illustrated in FIG. 1, as taken along the lines 2A-2A of FIG. 1;

FIG. 2B is an elevation view of another embodiment of an interfacemember;

FIG. 3 is an enlarged cross-sectional elevation view of one embodimentof the interface attachment means comprising the present invention;

FIG. 4 is an enlarged cross-sectional elevation view of anotherembodiment of the interface attachment means comprising the presentinvention;

FIG. 5 is a view of an embodiment of a treatment appliance comprisingthe present invention, in which an embodiment of a treatment device,shown in perspective view, is placed over a wound on a body, and inwhich an embodiment of a vacuum system, depicted generally and shown inschematic elevation view, provides reduced pressure within the volumeunder a cover comprising the treatment device;

FIG. 6 is a view of an embodiment of a treatment appliance comprisingthe present invention, in which an embodiment of a treatment device,shown in perspective view from the side of and above the treatmentdevice, is positioned over a wound on a body, and in which an embodimentof a vacuum system, shown in elevational view, provides reduced pressurewithin the volume under a cover comprising the treatment device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In accordance with the present invention, a wound treatment appliance isprovided for treating a wound by applying reduced pressure (i.e.,pressure that is below ambient atmospheric pressure) to the wound in acontrolled manner for a selected time period in a manner that overcomesthe disadvantages of currently existing apparatus. One embodiment of afirst version of the invention is the treatment appliance 10 illustratedin FIG. 1. FIG. 1 is an exploded perspective view of a cover 20comprising the treatment appliance 10 from the side of and above thecover 20 as it appears when applied to a portion of the body 16 of apatient surrounding a wound 15. In this embodiment, the cover 20 iscomprised of a top cup member 21, an interface member 22, and interfaceattachment means, which are described in more detail below, to attachthe interface member 22 to the top cup member 21. This embodiment alsocomprises sealing means to seal the cover 20 to the portion of the body16 surrounding the wound 15, which are described in more detail below,and reduced pressure supply means (not illustrated), which are alsodescribed in more detail below. The cover 20 is generally sized to beplaced over and enclose the wound 15 to be treated. The cover 20 and thesealing means (described in more detail below) allow reduced pressure tobe maintained in the volume under the cover 20 at the site of the wound15 to be treated, as described in more detail below. The reducedpressure supply means are used to operably connect the cover 20 to areduced pressure supply source (also not illustrated) in a manner sothat the reduced pressure supply source provides a supply of reducedpressure to the cover 20, so that the volume under the cover 20 at thesite of the wound 15 may be maintained at reduced pressure. It is to benoted, however, that in other embodiments of the present invention, thetop cup member 21 may be used for treatment of a wound 15 without theinterface member 22. In these embodiments, the top cup member 21 aloneis placed over the wound 15 and reduced pressure is applied to thevolume under the top cup member 21.

The embodiment of the top cup member 21 of the cover 20 illustrated inFIG. 1 is further comprised of a lid member 23 and a cup body member 24.In this embodiment, the lid member 23 is removably or permanentlyattached to the cup body member 24 using lid attachment means, which maybe substantially the same as any of the interface attachment means,which are described in more detail below. While the lid member 23 isattached to the cup body member 24, the lid attachment means provides agas-tight and liquid-tight seal so that reduced pressure may bemaintained in-the volume under the cover 20 in the area of the wound 15.In the embodiment illustrated in FIG. 1, the top cup member 21 isapproximately cylindrical in shape. In other embodiments of this firstversion of the present invention, the top cup member 21 may be of almostany shape or combination of shapes, as long as the open end 23 a of thelid member 23 is of a size and shape adapted to fit against a portion ofthe surface of the cup body member 24 in a manner so that an airtightand liquid-tight seal can be maintained by the use of the lid attachmentmeans, as described in more detail below. For example, as illustrated inFIG. 5, the top cup member 121 of the cover 120 may be approximatelycup-shaped, having an interface member 122 disposed on its bottomsurface. As other examples, the cover 20, 120 may be cubical, spherical,spheroidal, hexahedral, polyhedral, or arcuate in shape, or may becomprised of any combination of such shapes, in other embodiments. Thus,referring again to FIG. 1 as an example, the lid member 23 may also beshaped approximately as a hemisphere or a cone in other embodiments. Asanother example, in yet other embodiments, the cup body member 24 andthe open end 23 a of the lid member 23 may have a cross-section ofapproximately elliptical, square, rectangular, polygonal, arcuate orother shape or combination of all such shapes. The preferred shape andsize of the top cup member 21, 121, as well as the size and shape of anylid member 23 comprising it, are dependent upon the materials comprisingthe cover 20, 120, the thickness of the cover 20, 120, the nature of thewound to be treated, the size, shape and contour of the portion of thebody to be covered by the cover 20, 120, the magnitude of the reducedpressure to be maintained under the cover 20, 120, the size, shape andother aspects of the interface portion 22, 122, the individualpreferences of the user of the cover 20, 120, and other factors relatedto access to the wound 15, the sealing means, and the reduced pressuresupply means, as described in more detail below.

In the embodiment of the cover 20 illustrated in FIG. 1, the lid member23 may be detached from the cup body member 24. This allows the user ofthe appliance 10 to have access to the area of the wound 15 withouthaving to break the sealing means used to operably seal the cover 20 tothe portion of the body 16 surrounding the wound 15. The ability toaccess the wound 15 in this manner results in more efficient use of thetime of healthcare practitioners and less discomfort to patients. It isto be noted that in other embodiments, the lid member 23 and the cupbody member 24 may be permanently attached together or may be formed asa single piece. For example, the top cup member 121 of the cover 120 ofFIG. 5 does not have a detachable lid member, but is instead formed as asingle piece. In these embodiments, and referring to the cover 20 ofFIG. 1 as an example, the lid member 23 and the cup body member 24 maybe fabricated as a single piece, such as by injection molding, or theymay be attached together by any appropriate means, such as by welding,fusing, adhesives, glues, bolts, screws, pins, rivets, clamps, or otherfasteners or means or combinations of all such means. In the embodimentof the present invention illustrated in FIG. 1, the lid member 23 andthe cup body member 24 are each constructed of a material that is rigidenough to support the cover 20 away from the wound 15. Thus, the lidmember 23 and the cup body member 24 of the cover 20 may be comprised ofalmost any rigid or semi-rigid medical grade material that is currentlyknown in the art or that may be developed in the art in the future, aslong as such material is liquid-impermeable, suitable for purposes ofwound treatment (e.g., can be sterilized and does not absorb significantamounts of fluids, such as wound exudate), and is capable of supportingthe cover 20 away from the wound 15. For example, the lid member 23 andthe cup body member 24 may each be comprised of rubber (includingneoprene), metal, wood, paper, ceramic, glass, or rigid or semi-rigidpolymer materials, such as polypropylene, polyvinyl chloride, silicone,silicone blends, or other polymers or combinations of all such polymers.It is to be noted that in various embodiments of this first version ofthe invention, the lid member 23 and the cup body member 24 may beconstructed in whole or in part of gas-permeable materials, allowinglimited amounts of oxygen to penetrate the lid member 23 and the cupbody member 24 so that the portion of the body under the cover 20 in thearea of the wound 15 can “breathe.” In some embodiments, all portions ofthe top cup member 21 are preferably constructed of one type ofsemi-rigid material, such as polypropylene. In other embodiments, thetop cup member 21 may be constructed of more than one material. Forexample, the lid member 23 may be constructed of silicone and the cupbody member 24 of the cover 20 may be comprised of polyvinyl chloride,so that the lid member 23 may be stretched enough to overlap and sealagainst the outer edge of the cup body member 24 to form an operableseal, as described in more detail below. The preferred wall thickness ofthe cover 20 and its various component parts is dependent upon the sizeand shape of the cover 20, the size, shape and contour of the portion ofthe body to be covered by the cover 20, the magnitude of the reducedpressure to be maintained under the cover 20, the materials comprisingthe cover 20, and the individual preferences of the user of the cover20. For example, in the embodiment of the cover 20 illustrated in FIG.1, for a top cup member 21 constructed entirely of a silicone blend andhaving an approximate diameter of 4 inches and an approximate height of3 inches, the preferred wall thickness of the top cup member 21 is inthe range from 1/32 inches to ⅜ inches. It is to be noted that in otherembodiments the wall thickness of the various portions of the top cupmember 21 may vary from embodiment to embodiment, as well as fromportion to portion of the top cup member 21. Generally, the top cupmember 21 of the illustrated embodiment may be constructed using anysuitable means currently known in the art or that may be developed inthe art in the future. For example, a top cup member 21 constructedentirely of a silicone blend may be manufactured by means of injectionmolding. As another example, embodiments of covers 20 constructed ofdifferent types of materials may be constructed in the manner describedabove in this paragraph. It is to be noted that embodiments of the topcup member 121 comprised of one piece, without separate lid member andcup body member as illustrated by the cover 120 of FIG. 2, the top cupmember may be constructed of substantially the same materials, have thesame wall thicknesses, and be constructed in substantially the samemanner as described above in this paragraph.

In some embodiments of this first version of the present invention, asillustrated in FIG. 1, the cover 20 further comprises a port 25. Theport 25 is adapted to be of a size and shape so that the reducedpressure supply means may be operably connected to the top cup member 21by means of the port 25. When the port 25 is operably connected to thereduced pressure supply means, reduced pressure may be supplied to thevolume under the cover 20 at the site of the wound 15 to be treated.Although the port 25 is positioned at a location near one side of thelid member 23 of the enclosure 20 in the embodiment illustrated in FIG.1, the port 25 may be located at other positions on the top cup member21 (on either the lid member 23 or the cup body member 24) in otherembodiments, as long as the port 25 does not adversely affect theability of the cup body member 24 to form an operable seal with the lidmember 23 or the interface member 22, as described in more detail below.Although the port 25 may be constructed of a material different from thematerial comprising the remainder of the top cup member 21 in variousembodiments of the invention, the port 25 is preferably constructed fromthe same material comprising the top cup member 21 of the cover 20. Inthe embodiment of the cover 20 illustrated in FIG. 1, the port 25 isgenerally cylindrical in shape and is further comprised of anapproximately cylindrical channel 25 a that extends from the top of theport 25 to the bottom of the port 25. The port 25 of this embodiment isthus able to receive a vacuum system or reduced pressure supply means,which are described in more detail below, adapted to be connected tothis shape of port 25 and channel 25 a. In other embodiments of thisfirst version of the invention, the port 25 or the channel 25 a or bothmay have different shapes and configurations as may be desired to adaptand connect the port 25 and the channel 25 a to the vacuum system orreduced pressure supply means, which are described in more detail below.In some of the embodiments comprising a port 125, as illustrated in theembodiment of the cover 120 of FIG. 5, the top cup member 121 may befurther comprised of flow shutoff means (a one-way valve 129 in thisembodiment), which are operably connected to the port 125 and describedin more detail below. Referring again to FIG. 1 as an example, in otherembodiments of this first version of the invention, a means ofconnecting the top cup member 21 to the reduced pressure supply means(described in more detail below) may be located on the top cup member 21in lieu of or in conjunction with the port 25. For example, in someembodiments, the port 25 may be combined with a variable descendingdiameter adapter (commonly referred to as a “Christmas tree” adapter), aluer lock fitting, or other similar adapter or fitting.

In the embodiment of the cover 20 illustrated in FIG. 1, the interfacemember 22 is removably attached to the cup body member 24 by theinterface attachment means (described in more detail below), which areused to make an approximately airtight and liquid-tight seal with thetop cup member 21. In the illustrated embodiment, the interface member22 is comprised of a border portion 26, a membrane portion 27, andmembrane flow control means, which are described in more detail below.The membrane portion 27 in the illustrated embodiment has anapproximately flat surface and is approximately circular in shape whenviewed from above. In other embodiments, the membrane portion 27 mayhave other shapes. For example, the surface of the membrane portion 27may have a curved surface, so that it is concave (similar to a concavelens) in shape. In addition, the interface member 22 (and its borderportion 26 and membrane portion 27) may be of almost any shape and size,as long as the interface member 22 is of a size and shape adapted sothat it fits against a portion of the surface of the top cup member 21in a manner so that an approximately airtight and liquid-tight seal ismaintained by the interface attachment means, as described in moredetail below. For example, when viewed from above, the interface member22 may have an approximately elliptical, square, rectangular, polygonal,arcuate or other shape or combination of all such shapes. As anotherexample, as illustrated in the embodiment of the interface member 22 aof the cover 20 a illustrated in FIG. 2B, when viewed from the side, theinterface member 22 a may appear to have an approximately curved surfaceso that it may rest on portions of the body that have an approximatelycurved surface. Thus, in the illustrated embodiment, the border portion26 a has a generally flat top surface and an approximately concave lowersurface bounding the membrane portion 27 a. Also in this embodiment, theinterface member 22 a is removably attached to the cup body portion 24 aof the top cup member 21 a using the interface attachment means, whichare described in more detail below. It is to be noted that in someembodiments, as illustrated by the embodiment of the cover 120 in FIG.5, the top surface of the border portion 126 of the interface member 122may be positioned adjacent to the bottom surface of the top cup member121. The preferred shape and size of the interface member 22, 22 a, 122,as well as the size and shape of the border portion 26, 26 a, 126 andmembrane portion 27, 27 a, 127 comprising it, are dependent upon thesize and shape of the top cup member 21, 21 a, 121, materials comprisingthe cover 20, 120, the thickness of the interface member 22, 22 a, 122,the nature of the wound to be treated, the size, shape and contour ofthe portion of the body to be covered by the cover 20, 20 a, 120, themagnitude of the reduced pressure to be maintained under the cover 20,20 a, 120, the individual preferences of the user of the cover 20, 20 a,120, and other factors related to the sealing means and interfaceattachment means, as described in more detail below.

In the embodiment of the present invention illustrated in FIG. 1, theborder portion 26 is constructed of a material that is rigid enough tosupport the interface member 22 and the cover 20 away from the wound.Thus, the border portion 26 of the cover 20 may be comprised of almostany rigid or semi-rigid medical grade material that is currently knownin the art or that may be developed in the art in the future, as long assuch material is liquid-impermeable, suitable for purposes of woundtreatment (e.g., can be sterilized and does not absorb significantamounts of fluids, such as wound exudate), and is capable of supportingthe cover 20 away from the wound. For example, the border portion 26 maybe comprised of rubber (including neoprene), metal, wood, paper,ceramic, glass, or rigid or semi-rigid polymer materials, such aspolypropylene, polyvinyl chloride, silicone, silicone blends, or otherpolymers or combinations of all such polymers. In the illustratedembodiment, the membrane portion 27 is constructed of a material that isstrong enough to support the membrane flow control means, which aredescribed in more detail below. Thus, the membrane portion 27 of thecover 20 may be comprised of almost any rigid, semi-rigid, or flexiblemedical grade material that is currently known in the art or that may bedeveloped in the art in the future, as long as such material isliquid-impermeable, suitable for purposes of wound treatment (e.g., canbe sterilized and does not absorb significant amounts of fluids, such aswound exudate), and is capable of supporting the membrane flow controlmeans, which are described in more detail below. For example, themembrane portion 27 may be comprised of rubber (including neoprene),metal, wood, paper, ceramic, glass, or rigid or semi-rigid polymermaterials, such as polypropylene, polyvinyl chloride, silicone, siliconeblends, or other polymers or combinations of all such polymers. It is tobe noted that in various embodiments of this first version of theinvention, the interface member 22 may be constructed in whole or inpart of gas-permeable materials, allowing limited amounts of oxygen topenetrate the interface member 22 so that the portion of the body underthe cover 20 can “breathe.” In some embodiments, all portions of theinterface member 22 are preferably constructed of one type of semi-rigidmaterial, such as polypropylene. In other embodiments, the interfacemember 22 may be constructed of more than one material. For example, themembrane portion 27 may be constructed of silicone and the borderportion 26 of the cover 20 may be comprised of polyvinyl chloride, sothat the membrane portion 27 may be more flexible than the borderportion 26. The preferred wall thickness of the interface member 22 andits various component parts is generally dependent upon the sameparameters as described above for the top cup member 21. Although theinterface member 22 need not be constructed of the same materials as thetop cup member 21, it is preferred that the interface member 22 beconstructed of the same materials as the top cup member 21. Generally,the interface member 22 of the illustrated embodiment may be constructedusing any suitable means currently known in the art or that may bedeveloped in the art in the future. For example, an interface member 22constructed entirely of one material may be manufactured by means ofinjection molding. As another example, the component parts of aninterface member 22 constructed of different types of materials may beattached together by any appropriate means, such as by welding, fusing,adhesives, glues, bolts, screws, pins, rivets, clamps, or otherfasteners or other means or combinations of all such means.

Referring to the embodiment of the cover 20 illustrated in FIG. 1, theinterface member 22 is further comprised of membrane flow control means,which allow exudate aspirated from the wound 15 to flow into the volumeof the top cup member 21, but not in the opposite direction. In theillustrated embodiment, the membrane flow control means is comprised ofeight flow control valves 28. It is to be noted that in variousembodiments the flow control valves 28 may be any type of valvecurrently known in the relevant art or that may be developed in therelevant art in the future that is suitable for operation in reducedpressure environments that allows fluids to flow in one directionthrough the valve, but not in the opposite direction. For example, suchvalves 28 may generally be comprised of sprung or unsprung flapper ordisc-type valves. In the illustrated environment, the flow controlvalves 28 are comprised of flapper-type valves, which are each furthercomprised of two flappers that are approximately semi-circular in shapeand hinged at their outside edge so that when they fall together theyform a seal that only allows fluids to flow in one direction (from thewound 15 to the volume within the top cup member 21 in this embodiment).Although the interface member 22 may have at least one flow controlvalve 28 in some embodiments, the interface member 22 may have almostany number of flow control valves 28 in other embodiments. For example,as illustrated in FIG. 5, the interface member 122 may be comprised oftwo flow control valves 128. In embodiments of the present inventioncomprising flow control valves 28, the preferred number and type ofvalves 28 is dependent upon the shape and size of the interface member22, the materials comprising the interface member 22, the thickness ofthe membrane portion 27, the nature of the wound 15 to be treated, theamount of exudate anticipated, the size, shape and contour of theportion of the body to be covered by the cover 20, the magnitude of thereduced pressure to be maintained under the cover 20, the individualpreferences of the user of the cover 20, and other factors related tothe sealing means, as described in more detail below. It is to be notedthat in some embodiments, the flow control valves 28 may be formed froma single piece with the membrane portion 27, or may be attached to themembrane portion 27 using any suitable means, such as by welding,fusing, adhesives, glues, bolts, screws, pins, rivets, clamps, or otherfasteners or means or combinations of all such means. In otherembodiments, the membrane flow control means may be comprised of amembrane portion 27 that is constructed in whole or in part of amaterial that allows fluids to flow in one direction, but not in theopposite direction. In these embodiments, exudate from the wound 15flows from the wound 15 through the membrane portion 27 (or a portionthereof) to the volume within the top cup member 21, but does not flowin the reverse direction back to the wound 15.

In various embodiments of this first version of the present invention,the interface attachment means, which may be used to removably orpermanently attach the interface member 22 to the top cup member 21, maybe any suitable means currently known in the relevant art or developedin the relevant art in the future that may be used to create an airtightand liquid-tight seal (sometimes referred to herein as an “operableseal”) between the interface member 22 and the top cup member 21. Forexample, in the embodiment illustrated in FIG. 3, which is an enlargedcross-sectional elevation view of an interface attachment means, theborder portion 26 b is constructed of a semi-rigid material (such assilicone) and has a lip portion 26 b′ that extends around the perimeterof the interface member 22 b. The cup body member 24 b of the top cupmember 21 b also has a lip portion 24 b′ adjacent to the bottom edge ofthe cup body member 24 b that extends around the perimeter of the bottomedge of the cup body member 24 b. In this embodiment, the interfaceattachment means is comprised of the lip portion 26 b′ of the interfacemember 22 b being stretched over the lip portion 24 b′ of the top cupmember 21, so that the lip portions are joined tightly together to forman operable seal. As another example, as illustrated in FIG. 4, theinterface attachment means may be comprised of an o-ring (or gasket orsimilar sealing means) 26 c′ that is positioned in a groove extendingaround the perimeter of the border portion 26 c or the cup body member24 c or both, so that the o-ring 26 c′ forms an operable seal betweenthe top cup member 21 c and the interface member 22 c. Referring againto FIG. 1 as an example, in still other embodiments, the exterior bottomportion of the cup body member 24 may be threaded and the interiorbottom portion of the border portion 26 of the interface member 22 maybe of a structure to receive such threads, so that an operable seal iscreated when the cup body member 24 is screwed into the interface member22. In yet other embodiments, as illustrated in FIG. 5, the interfaceattachment means may be comprised of a magnetic strip (not shown)attached to the bottom surface 124 a of the cup body member 124 of thetop cup member 121 and to the top surface 126 a of the border portion126 of the interface member 122, so that such surfaces abut against oneanother in the manner illustrated in FIG. 5 when the surfaces areattracted by magnetic force, creating an operable seal. Further, theinterface attachment means may be comprised of a washer, gasket, o-ringor similar structure (not shown) attached to the bottom surface 124 a ofthe cup body member 124 of the top cup member 121 or to the top surface126 a of the border portion 126 of the interface member 121, or both, sothat such surfaces abut against one another in the manner illustrated inFIG. 5, creating an operable seal. In these embodiments, the top cupmember 121 may be held in place against the interface member 122 bymeans of clips, brackets, pins, clamps, clasps, adhesives, adhesivetapes, quick-release or other fasteners, or combinations of such means.In addition, many types of sealing means that may be used to removablyattach components of kitchenware-type items together may by used as theinterface attachment means. It is also to be noted that in otherembodiments the interface attachment means may be comprised of means topermanently attach the interface member 22 to the top cup member 21 orof forming the interface member 22 and the top cup member 21 as a singlepiece. In these embodiments, and referring to the cover 20 of FIG. 1 asan example, the interface member 22 and the top cup member 21 may befabricated as a single piece, such as by injection molding, or they maybe attached together by any appropriate means, such as by welding,fusing, adhesives, glues, bolts, screws, pins, rivets, clamps, or otherfasteners or means or any combinations of all such means. Referringagain to FIG. 1 as an example, it is to be noted that the lid attachmentmeans that may be used to removably or permanently attach the lid member23 to the cup body member 21 may have substantially the same structure,features, characteristics and operation as any or all of the embodimentscomprising the interface attachment means described above.

An embodiment of a second version of the present invention is thetreatment appliance 110 illustrated in FIG. 5. In this embodiment, thetreatment appliance 110 is comprised of a treatment device 111 and avacuum system, generally designated 150, which is operably connected to,and provides a supply of reduced pressure to, the treatment device 111.Also in this embodiment, the treatment device 111 is comprised of acover 120. In addition, in this embodiment, the vacuum system 150 isfurther comprised of a reduced pressure supply source, generallydesignated 130, which is illustrated schematically and described in moredetail below, and reduced pressure supply means, generally designated140, which are described in more detail below. Also in this embodiment,the reduced pressure supply means 140 are used to connect the reducedpressure supply source 130 to the cover 120 in a manner so that reducedpressure is supplied to the volume under the cover 120 at the site ofthe wound 115 to be treated, as described in more detail below. In theembodiment of the second version of the invention illustrated in FIG. 5,the illustrated cover 120 is comprised of a top cup member 121, aninterface member 122, and interface attachment means to removably attachthe top cup member 121 to the interface member 122. In the illustratedembodiment, the interface attachment means is comprised of a magneticstrip (not shown) on the top surface 126 a of the border portion 126 ofthe interface member 122 and a magnetic strip (not shown) on the bottomsurface 124 a of the cup body member 124 of the top cup member 121. Anoperable seal is formed between the interface member 122 and the top cupmember 121 by the magnetic attraction of the magnetic strips. In otherembodiments, the interface attachment means may be comprised of any ofthe interface attachment means of the first version of the presentinvention illustrated and described above in connection with FIG. 1through FIG. 5. Alternatively, the interface member 122 and the top cupmember 121 may be formed as a single piece or permanently attached, asillustrated and described above in connection with FIG. 1 through FIG.5. It is to be noted that in this and other embodiments of this secondversion of the invention, the cover 120 may have substantially the samestructure, features, characteristics and operation as any embodiment ofany of the covers 20, 20 a, 120 of the first version of the inventiondescribed above and illustrated in connection with FIG. 1 through FIG.5. It is also to be noted that in other embodiments of the presentinvention, the top cup member 121 may be used for treatment of a wound115 without the interface member 126. In these embodiments, the top cupmember 121 alone is placed over the wound 115 and reduced pressure isapplied to the volume under the top cup member 121.

In the various embodiments of this second version of the presentinvention, as illustrated in FIG. 5, the interface member 122 of thecover 120 may be comprised of a semi-rigid material and the sealingmeans may be comprised of the suction of the interface member 122against the portion 116 of the body adjacent to the interface member 122of the cover 120, such suction being produced by the presence of reducedpressure in the volume under the cover 120 at the site of the wound 115.In other embodiments, the sealing means may be comprised of an adhesive,an adhesive tape, lanoline, or other sealant, or any combination of suchmeans, that is disposed between the interface member 122 and the portion116 of the body adjacent to the interface member 122 or disposed overthe interface member 122 and the portion of the body outside theperimeter of the interface member 122. In yet other embodiments, thesealing means may be comprised of a material (not illustrated) that ispositioned approximately over the cover 120 and wrapped around theportion 116 of the body on which the cover 120 is positioned. Thismaterial is used to hold the cover 120 against the adjacent portion 116of the body. For example, if the wound 115 were on the patient's leg, anelastic bandage or adhesive tape may be wrapped over the cover 120 andaround the leg.

In the embodiment illustrated in FIG. 5, the reduced pressure supplysource 130 of the vacuum system 150, which produces a source of reducedpressure or suction that is supplied to the cover 120, is comprised of avacuum pump 131, a control device 132, and a filter 133. Although thepreferred means of producing the reduced pressure or suction is a vacuumpump 131 in this embodiment, in other embodiments of this second versionof the invention other means may be used, such as an outlet port of acentralized hospital vacuum system. In the illustrated embodiment,predetermined amounts of suction or reduced pressure are produced by thevacuum pump 131. The vacuum pump 131 is preferably controlled by acontrol device 132, such as a switch or a timer that may be set toprovide cyclic on/off operation of the vacuum pump 131 according touser-selected intervals. Alternatively, the vacuum pump 131 may beoperated continuously without the use of a cyclical timer. In addition,in some embodiments the control device 132 may provide for separatecontrol of the level of reduced pressure applied to the volume under thecover 120 at the site of the wound 115 and the flow rate of fluidaspirated from the wound 115, if any. In these embodiments, relativelylow levels of reduced pressure may be maintained at the site of thewound 115 in the volume under the treatment device 111, while stillproviding for the removal of a relatively large volume of exudate fromthe wound 115. A filter 133, such as a micropore filter, is preferablyattached to the inlet of the vacuum pump 131 to prevent potentiallypathogenic microbes or aerosols from contaminating, and then beingvented to atmosphere by, the vacuum pump 131. In other embodiments, thefilter 133 may also be a hydrophobic filter that prevents any exudatefrom the wound 115 from contaminating, and then being vented toatmosphere by, the vacuum pump 131. It is to be noted that in otherembodiments of the invention, the reduced pressure supply source 130 maynot have a filter 133 or a control 132 or any combination of the same.

In other embodiments of the second version of the invention, the reducedpressure supply source 130 of the vacuum system 150, may be comprised ofa small, portable vacuum pump 131. In some of these embodiments, afilter 133 or a power source (not illustrated), or both, may also becontained within the housing for the portable vacuum pump 131. In theseembodiments, the portable vacuum pump 131 is preferably controlled by acontrol device 132 that is also located within the housing for theportable vacuum pump 131, which may provide substantially the samefunctions as the control device 132 described above. Except for itssmaller size, the portable vacuum pump 131 may operate in substantiallythe same manner as the vacuum pump 131 described above. Also, in theseembodiments, the filter 133 may have the same structure, features,characteristics and operation, and provide substantially the samefunctions, as the filter 133 described above. In some of theseembodiments, the filter 133 may be rigidly connected to the portablevacuum pump 131. The power source may be any source of energy currentlyknown in the art or that may be developed in the art in the future thatmay be used to power the portable vacuum pump 131. For example, in someembodiments, the power source may be a fuel cell, battery or connectionto a standard wall electrical outlet.

In the embodiment of the second version of the invention illustrated inFIG. 5, the reduced pressure supply means 140 of the vacuum system 150,which are used to connect the reduced pressure supply source 130 to thecover 120 so that reduced pressure is supplied to the volume under thecover 120 at the site of the wound 115, is comprised of at least onetubing member 141. In this embodiment, the at least one tubing member141 is sufficiently flexible to permit movement of the at least onetubing member 141, but is sufficiently rigid to resist constriction whenreduced pressure is supplied to the cover 120 or when the location ofthe wound 115 is such that the patient must sit or lie upon the at leastone tubing member 141 or upon the treatment device 111. In theembodiment illustrated in FIG. 5, the at least one tubing member 141 isconnected to the cover 120 by inserting one end of the at least onetubing member 141 into an opening 125 a of a port 125 of the cover 120.In this embodiment, the at least one tubing member 141 is held in placein the opening 125 a by means of an adhesive. It is to be noted that inother embodiments of this second version of the invention, the at leastone tubing member 141 may be connected to the port 125 of the cover 120using any suitable means currently known in the art or developed in theart in the future. Examples include variable descending diameteradapters (commonly referred to as “Christmas tree” adapters), luer lockfittings and adapters, clamps, and combinations of such means.Alternatively, the port 125 and the at least one tubing member 141 maybe fabricated as a single piece. Similar means may be used to connectthe other end of the at least one tubing member 141 to the vacuum pump131 or other reduced pressure supply source 130 providing the reducedpressure.

In the embodiment of the second version of the present inventionillustrated in FIG. 5, the treatment device 111 functions to activelydraw fluid or exudate from the wound 115 through two flow control valves128 positioned on the membrane portion 127 of the interface member 122into the interior volume of the cover 120. In this embodiment, it isgenerally desirable to collect exudate in the interior volume of thecover 120, but not to allow the exudate to flow into the reducedpressure supply means 140 in order to prevent clogging of the vacuumpump 131. In addition, it is desirable to halt or inhibit the supply ofreduced pressure to the cover 120 in the event that the exudateaspirated from the wound 115 exceeds a predetermined quantity. Further,it is desirable to interrupt the application of suction to the cover 120to prevent exsanguination in the unlikely event a blood vessel rupturesunder the cover 120 during treatment. If, for example, a blood vesselruptures in the vicinity of the cover 120, a shutoff mechanism would beuseful to prevent the vacuum system 150 from aspirating any significantquantity of blood from the patient. As a result, the top cup member 121in the illustrated embodiment is further comprised of flow shutoffmeans. In this embodiment, the flow shutoff means is comprised of aflapper-type valve 129, which is generally comprised of a flapper 129 athat is hinged to an interior surface of the port 125 and seats againsta stop 129 b. The flapper 129 a is buoyant when compared to the exudate,so that it floats upon the exudate as the level of exudate in the volumeof the cover 120 rises to the level of the flapper valve 129. Theflapper 129 a is, however, heavy enough not to be drawn against the stop129 b when reduced pressure is applied to the cover 120 by the vacuumsystem 150. Thus, as the exudate level rises to the level of the stop129 b, the flapper 129 a floats upon the exudate until the flapper 129 aseats against the stop 129 b, which seals the cover 120 so that reducedpressure is no longer supplied to the cover 120 by the vacuum system150. In other embodiments, the flow shutoff means may be comprised ofalmost any other type of shutoff valve currently known in the relevantart or that may be developed in the relevant art in the future that issuitable for this purpose and use in a reduced pressure environment.Another example of such valve is a float valve, wherein a float ballfloats upon the exudate so that the float ball seals against a seat whenthe level of exudate reaches a predetermined level. All such valves arewell known in the relevant art. In other embodiments, other types ofmechanisms may also be employed to detect the liquid level within thecover 120 in order to arrest operation of the vacuum system 150. Inaddition, in various embodiments of this second version of theinvention, the flow shutoff means may be comprised of any means thatenables the vacuum system 150 to halt the supply of reduced pressure tothe cover 120 at any time that the volume of exudate from the wound 115exceeds a predetermined amount. Such means may include mechanicalswitches, electrical switches operably connected to the vacuum systemcontroller 132, optical, thermal or weight sensors operably connected tothe vacuum system controller 132, and any other means that are currentlyknown in the relevant art or that may be developed in the relevant artin the future.

In some embodiments of this second version of the invention, thetreatment device 111 further comprises tissue protection means (notillustrated) to protect and strengthen the surface tissue of theportions 116 of the body that are adjacent to the cover 120. The tissueprotection means protects such tissue by preventing abrasion andmaceration of the tissue. Preferably, the tissue protection means is ahydrocolloid material, such as COLOPAST Hydrocolloid 2655, anhydrouslanoline, or any combination of such hydrocolloid materials. Morepreferably, the tissue protection means is COLOPAST Hydrocolloid 2655.The tissue protection means may be applied to the body tissue to beprotected, or it may be applied to the surface of the cover 120 that isto be in contact with the body tissue 116, or both, prior to placing thecover 120 over the wound 115. It is to be noted that application of thetissue protection means to the body tissue 116 that is adjacent to thecover 120 at the site of the wound 115 may only entail application ofthe tissue protection means to the parts of the body tissue 116 adjacentto the cover 120 that require such protection.

Referring to FIG. 5, a method of using the treatment appliance 110 ofthe illustrated embodiment is also disclosed. In this example, the cover120 is removed from an aseptic package in which it is stored. Thevarious component parts of the cover are operably sealed together. Forexample, in the illustrated embodiment, the top cup member 121 isoperably sealed to the interface member 122. In embodiments where thetop cup member 21 further comprises a lid member 23 and a cup bodymember 24, as illustrated in FIG. 1, the lid member 23 and the cup bodymember 24 are also operably sealed together. Referring again to FIG. 5,this sealing of the component parts of the cover 120 may occur before,during or after the cover 120 is placed over the wound 115. The cover120 is placed over and encloses the wound 115. The cover 120 isconnected to the vacuum system 150 by means of the port 125 on the cover120 either before, after or during the placement of the cover 120 overthe wound 115. Where it is deemed necessary by the user of the treatmentappliance 110, tissue protection means, as described above, may beplaced on a portion of the cover 120, on the body tissue to beprotected, or both, prior to placing the cover 120 over the wound 115.Reduced pressure is then supplied to the cover 120 by the vacuum system150. In the illustrated embodiment, when reduced pressure is applied tothe volume under the cover 120 at the site of the wound 115, the cover120 is drawn downward by the reduced pressure so that the cover 120 isdrawn tightly against the surface of the adjacent portion 116 of thebody, thus forming an operable seal between the cover 120 and theportion 116 of the body adjacent to the cover 120. References to an“operable seal” and “sealing means” herein refer generally to a sealthat may be made gas-tight and liquid-tight for purposes of the reducedpressure treatment of the wound 115. It is to be noted that this sealneed not be entirely gas-tight and liquid-tight. For example, theoperable seal may allow for a relatively small degree of leakage, sothat outside air may enter the volume under the cover 120 at the site ofthe wound 115, as long as the degree of leakage is small enough so thatthe vacuum system 150 can maintain the desired degree of reducedpressure in the volume under the cover 120 at the site of the wound 115.As another example, the operable seal formed by the cover 120 may not besolely capable of maintaining the reduced pressure in the volume underthe cover 120 at the site of the wound 115 due to the shape of the bodyportion 116 at the site of the wound 115, due to the orientation of thewound 115, or due to some other reason. In these cases, as well as othercases, it may be necessary or desirable to provide other sealing means(not illustrated), which are described in more detail above. In someembodiments of the second version of the present invention comprising alid member 23, as illustrated by the cover 20 of FIG. 1, the method mayalso comprise one or more of the steps of halting the application ofreduced pressure to the cover 20, removing the lid member 23 from thecup body member 24, attending to the wound 115, re-attaching the lidmember 23 to the cup body member 24, and then reapplying reducedpressure to the volume under the cover 20 in the area of the wound 115.In yet other embodiments, and referring again to FIG. 5, the method maycomprise one or more of the steps of monitoring the fluid level 117 inthe volume within the cover 120, halting the application of reducedpressure to the cover 120 when the fluid level 117 reaches apredetermined level, removing the fluid in the volume within the cover120, and reapplying reduced pressure to the volume under the cover 20 inthe area of the wound 115. In the preferred embodiments of this secondversion of the invention, the reduced pressure maintained in the volumeunder the cover 120 at the site of the wound 115 is in the range fromapproximately 20 mm of Hg below atmospheric pressure to approximately125 mm of Hg below atmospheric pressure. In yet other embodiments, thereduced pressure is applied to the cover 120 in a cyclic nature, thecyclic nature providing alternating time periods of application ofreduced pressure and non-application of reduced pressure. In variousembodiments, the method also comprises the step of maintaining reducedpressure in the volume under the cover 120 at the site of the wound 115until the wound 115 has progressed toward a selected stage of healing.

An embodiment of a third version of the invention is the treatmentappliance 210 illustrated in FIG. 6. In this embodiment, the treatmentappliance 210 is comprised of a treatment device 211 and a vacuumsystem, generally designated 250, operably connected to, and providing asupply of reduced pressure to, the treatment device 211. In addition, inthis embodiment, the vacuum system 250 is further comprised of a reducedpressure supply source, generally designated 260, which is described inmore detail below, and reduced pressure supply means 240, which aredescribed in more detail below. Also in this embodiment, the treatmentdevice 211 is further comprised of a cover 220, which generally hassubstantially the same structure, features, and characteristics as theembodiment of the cover 120 illustrated and described above inconnection with FIG. 5. It is to be noted, however, that in otherembodiments of this third version of the invention, the cover 220 mayhave substantially the same structure, features, characteristics andoperation as any embodiment of all of the covers 20, 20 a, 120 of thefirst and second versions of the invention described above andillustrated in connection with FIG. 1 through FIG. 5. In the embodimentillustrated in FIG. 6, the cover 220 is placed over and encloses a wound215. In the illustrated embodiment, the cover 220 may be sealed to theadjacent portions 216 of the body using any of the sealing means oroperable seals described above and illustrated in connection with FIG.5.

In the embodiment of the third version of the invention illustrated inFIG. 6, the vacuum system 250 is generally comprised of a suction bulb261 having an inlet port 262 and an outlet port 263, a bulb connectiontubing member 264, an exhaust tubing member 265, an exhaust controlvalve 266, a filter 267, and a supplemental vacuum system (illustratedschematically and generally designated 250 a). In this embodiment, thesuction bulb 261 is a hollow sphere that may be used to produce a supplyof reduced pressure for use with the treatment device 211. In addition,in some embodiments, the suction bulb 261 may also be used to receiveand store exudate aspirated from the wound 215. The inlet port 262 ofthe suction bulb 261 is connected to one end of the bulb connectiontubing member 264, which is connected to the reduced pressure supplymeans 240, a tubing member in this embodiment, by means of a connector246. The connection tubing member 264 is connected to the reducedpressure supply means 240 in a manner so that the interior volume of thesuction bulb 261 is in fluid communication with the volume under thecover 220 in the area of the wound 215. In this embodiment, the bulbconnection tubing member 264 and the reduced pressure supply means 240are sufficiently flexible to permit movement of the bulb connectiontubing member 264 and the reduced pressure supply means 240,respectively, but are sufficiently rigid to resist constriction whenreduced pressure is supplied to the cover 220 or when the location ofthe wound 215 is such that the patient must sit or lie upon the bulbconnection tubing member 264, upon the reduced pressure supply means240, or upon the treatment device 311. The outlet port 263 of thesuction bulb 261 is connected to the exhaust tubing member 265. In thisembodiment, the exhaust tubing member 265 is sufficiently flexible topermit movement of the exhaust tubing member 265, but is sufficientlyrigid to resist constriction when reduced pressure is supplied to thecover 220. The inlet port 262 of the suction bulb 261 may be connectedto the bulb connection tubing member 264 and the outlet port 263 of thesuction bulb 261 may be connected to the exhaust tubing member 265 usingany suitable means, such as by welding, fusing, adhesives, clamps, orany combination of such means. In addition, in some embodiments, whichare the preferred embodiments, the suction bulb 261, the bulb connectiontubing member 264, and the exhaust tubing member 265 may be fabricatedas a single piece. In the illustrated embodiment, the exhaust controlvalve 266 and the filter 267 are operably connected to the exhausttubing member 265. In this embodiment, the exhaust control valve 266 isused to regulate the flow of fluids (gases and liquids) to and from thesuction bulb 261 and the supplemental vacuum system 250 a. Inembodiments of the invention that do not have a supplemental vacuumsystem 250 a, the exhaust control valve 266 regulates flow of fluids toand from the suction bulb 261 and the outside atmosphere. Generally, theexhaust control valve 266 allows fluids to flow out of the suction bulb261 through the outlet port 263, but not to flow in the reversedirection unless permitted by the user of the appliance 210. Any type offlow control valve may be used as the exhaust control valve 266, as longas the valve 266 is capable of operating in the anticipated environmentinvolving reduced pressure and wound 215 exudate. Such valves are wellknown in the relevant art, such as sprung and unsprung flapper-typevalves and disc-type valves, operating in conjunction with or withoutball, gate and other similar types of valves. In this embodiment, thefilter 267 is operably attached to the exhaust tubing member 265 betweenthe outlet port 263 of the suction bulb 261 and the exhaust controlvalve 266. The filter 267 prevents potentially pathogenic microbes oraerosols from contaminating the exhaust control valve 266 (andsupplemental vacuum system 250 a), and then being vented to atmosphere.The filter 267 may be any suitable type of filter, such as a microporefilter. In other embodiments, the filter 267 may also be a hydrophobicfilter that prevents any exudate from the wound 215 from contaminatingthe exhaust control valve 266 (and the supplemental vacuum system 250 a)and then being vented to atmosphere. In still other embodiments, thefilter 267 may perform both functions. It is to be noted, however, thatthe outlet port 263, the exhaust control valve 266, the filter 267, orany combination of the exhaust control valve 266 and the filter 267,need not be utilized in connection with the vacuum system 250 in otherembodiments of the invention.

In some embodiments of the third version of the invention illustrated inFIG. 6 that do not utilize a supplemental vacuum system 250 a, thesuction bulb 261 may be used to produce a supply of reduced pressure inthe following manner. First, the user of the appliance 210 appropriatelyseals all of the component parts of the appliance 210 in the mannerdescribed herein. For example, the top cup member 221 of the cover 220is operably sealed to the interface member 222 of the cover 220, and thecover 220 is placed over and encloses the wound 215. At least a portionof the interface member 222 is sealed (or placed adjacent) to theadjacent portions 216 of the body, and the reduced pressure supply means240 is connected to the bulb connection tubing member 264 by means ofthe connector 246. The user then opens the exhaust control valve 266 andapplies force to the outside surface of the suction bulb 261, deformingit in a manner that causes its interior volume to be reduced. When thesuction bulb 261 is deformed, the gas in the interior volume is expelledto atmosphere through the outlet port 263, the exhaust tubing member265, the filter 267, and the exhaust control valve 266. The user thencloses the exhaust control valve 266 and releases the force on thesuction bulb 261. The suction bulb 261 then expands, drawing gas fromthe area of the wound 215 under the treatment device 211 into thesuction bulb 261 and causing the pressure in such area to decrease. Torelease the reduced pressure, the user of the appliance 210 may open theexhaust control valve 266, allowing atmospheric air into the interiorvolume of the suction bulb 261. The level of reduced pressure may alsobe regulated by momentarily opening the exhaust control valve 266.

The suction bulb 261 may be constructed of almost any fluid impermeableflexible or semi-rigid material that is suitable for medical use andthat can be readily deformed by application of pressure to the outsidesurface of the suction bulb 261 by users of the appliance 210 and stillreturn to its original shape upon release of the pressure. For example,the suction bulb 261 may be constructed of rubber, neoprene, silicone,or other flexible or semi-rigid polymers, or any combination of all suchmaterials. In addition, the suction bulb 261 may be of almost any shape,such as cubical, ellipsoidal, or polyhedral. The suction bulb 261 mayalso be of varying size depending upon the anticipated use of thesuction bulb 261, the size of the wound treatment device 211, use of asupplemental vacuum system 250 a, the level of reduced pressure desired,and the preference of the user of the appliance 210. In the embodimentof the invention illustrated in FIG. 6, the supplemental vacuum system250 a is connected to the exhaust tubing member 265 and is used toprovide a supplemental supply of reduced pressure to the suction bulb261 and treatment device 211. In this embodiment, the supplementalvacuum system 250 a may have substantially the same structure, features,characteristics and operation of the various embodiments of the vacuumsystem 250 of the second version of the invention described above andillustrated in connection with FIG. 5. It is to be noted, however, thatthe supplemental vacuum system 250 a need not be used in connection withthe vacuum system 250 in other embodiments of the invention.

Except as illustrated and described above in connection with FIG. 6, thetreatment appliance 210 may generally be used in a manner similar to thetreatment appliance 110 described above and illustrated in connectionwith FIG. 5. As a result, except as described herein, the example of howthe embodiment of the treatment appliance 110 and the cover 120described above and illustrated in connection FIG. 5 may be used intreatment of a wound 115 also applies to the embodiment of the appliance210 of the third version of the invention described above andillustrated in connection with FIG. 6.

1. A method of treating a wound, comprising: positioning a membrane intocontact with the wound; positioning a wound cover over the wound, thecover having a rigid or semi-rigid ring sized to contact skinsurrounding the wound so as to create a relatively fluid-tight seal;applying reduced pressure to the wound through a port on the wound coverto draw fluid from the wound through the membrane; while reducedpressure is being applied to the wound, collecting fluid from the woundin a space between the cover and the membrane; and preventing thecollected fluid from flowing through the port.
 2. The method of claim 1,wherein a source of negative pressure positioned outside the coverapplies reduced pressure to the wound.
 3. The method of claim 1, whereinpositioning the cover comprises positioning a rigid or semi-rigid woundcover over the wound.
 4. The method of claim 1, further comprisingpositioning a tissue protection member adjacent the wound.
 5. The methodof claim 1, further comprising monitoring the volume underneath thecover.
 6. The method of claim 1, comprising utilizing a filterpositioned between the port and a source of reduced pressure.
 7. Themethod of claim 1, wherein the reduced pressure is applied with asuction pump.
 8. The method of claim 1, wherein the wound cover is rigidor semi-rigid and defines at least in part the space for the collectedfluid.
 9. A method for the treatment of a wound on a body, the methodcomprising: positioning a flexible membrane in contact with the body,the flexible membrane forming a seal with the body; placing a woundcover over the wound to enclose the wound, the wound cover forming areversible seal with the flexible membrane; and applying negativepressure to the wound through the wound cover and the flexible membrane;wherein the wound cover is removable from and resealably attached to theflexible membrane while the flexible membrane remains sealed with thebody.
 10. The method of claim 9, further comprising: stopping theapplication of negative pressure to the wound; removing the wound coverfrom the flexible membrane while the flexible membrane remains sealedwith the body.
 11. The method of claim 9, wherein the application ofnegative pressure draws and collects wound exudate into a chamberbetween the flexible membrane and the wound cover.
 12. The method ofclaim 11, further comprising detecting the amount of collected woundexudate.
 13. The method of claim 9, wherein a gasket is positionedbetween the flexible membrane and the wound cover, the gasket providinga liquid-tight seal between the wound cover and the flexible membrane.14. A method of treating a wound, comprising: positioning a membraneinto contact with the wound; positioning a wound cover over the wound,the cover having a rigid or semi-rigid ring sized to contact skinsurrounding the wound so as to create a relatively fluid-tight seal;applying reduced pressure to the wound through a port on the wound coverto draw fluid from the wound through the membrane; collecting fluid fromthe wound in a space between the cover and the membrane; and preventingthe collected fluid from flowing through the port; wherein creating arelatively fluid-tight seal comprises positioning an o-ring seal orgasket between the cover and the wound.
 15. The method of claim 14,further comprising utilizing a filter to prevent collected fluid fromflowing past the filter.
 16. The method of claim 15, wherein the filtercomprises a hydrophobic filter.
 17. The method of claim 14, wherein thereduced pressure is applied with a suction pump.
 18. The method of claim14, wherein the rigid or semi-rigid ring comprises the o-ring seal orgasket.
 19. The method of claim 14, further comprising positioning atissue protection member adjacent the wound.
 20. The method of claim 14,wherein the wound cover is flexible.
 21. A method of treating a wound,comprising: positioning a membrane into contact with the wound;positioning a wound cover over the wound, the cover sized and configuredto contact skin surrounding the wound so as to create a relativelyfluid-tight seal; applying reduced pressure to the wound through a porton the wound cover to draw fluid from the wound through the membrane;collecting fluid from the wound in a chamber between the cover and themembrane; preventing the collected fluid from flowing through the port;removing the chamber when it is filled with wound exudate; andsubsequently positioning a second chamber between a second cover and thewound.
 22. The method of claim 21, wherein the wound cover is attachedto the membrane.
 23. A method of treating a wound, comprising:positioning a membrane into contact with the wound; positioning a woundcover over the wound, the cover sized and configured to contact skinsurrounding the wound so as to create a relatively fluid-tight seal;applying reduced pressure to the wound through a port on the wound coverto draw fluid from the wound through the membrane using a source ofreduced pressure; collecting fluid from the wound in a space between thecover and the membrane; and preventing the collected fluid from flowingthrough the port by using an overflow mechanism positioned at the port.24. The method of claim 23, wherein preventing fluid from the wound fromflowing through the port comprises operating a valve positioned at theport.
 25. The method of claim 23, further comprising utilizing a filterto prevent collected fluid from flowing past the filter.
 26. The methodof claim 23, wherein the overflow mechanism comprises a flapper-typevalve.
 27. The method of claim 23, wherein a flow shutoff means preventscollected fluid from flowing through the port.
 28. The method of claim27, further comprising halting the application of reduced pressure whenthe flow shutoff means prevents collected fluid from flowing through theport.
 29. The method of claim 23, wherein the membrane permits woundexudate to flow in a direction away from the wound, but does not permitwound exudate to flow in the opposite direction.
 30. The method of claim23, further comprising positioning a tissue protection member adjacentthe wound.
 31. A method of treating a wound, comprising: positioning amembrane into contact with the wound; positioning a wound cover over thewound, the cover sized and configured to contact skin surrounding thewound so as to create a relatively fluid-tight seal; applying reducedpressure to the wound through a port on the wound cover to draw fluidfrom the wound through the membrane; collecting fluid from the wound ina space between the cover and the membrane; preventing the collectedfluid from flowing through the port, and preventing the collected fluidfrom flowing back through the membrane into the wound.
 32. The method ofclaim 31, wherein the membrane permits wound exudate to flow into thespace, but does not permit wound exudate to flow in the oppositedirection.
 33. The method of claim 31, wherein the membrane is attachedto the wound cover.
 34. The method of claim 33, wherein the membranecomprises one or more flow control valves.
 35. The method of claim 31,further comprising utilizing a filter to prevent collected fluid fromflowing past the filter.
 36. The method of claim 31, wherein themembrane permits wound exudate to flow in a direction away from thewound, but does not permit wound exudate to flow in the oppositedirection.
 37. A method of treating a wound, comprising: positioning amembrane into contact with the wound; positioning a wound cover over thewound, the cover sized and configured to contact skin surrounding thewound so as to create a relatively fluid-tight seal; applying reducedpressure to the wound to draw fluid from the wound through the membrane;collecting fluid from the wound at a location between the membrane andthe cover; and preventing the collected fluid from flowing out of thecover while reduced pressure is being applied to the wound.
 38. Themethod of claim 37, wherein the reduced pressure is applied from asource of negative pressure connected to the wound cover via a port onthe wound cover.
 39. The method of claim 38, wherein the source ofnegative pressure is connected to the port using a conduit.
 40. Themethod of claim 37, further comprising monitoring the volume ofcollected fluid underneath the cover.
 41. The method of claim 40,further comprising ceasing the application of reduced pressure once thevolume of collected fluid has exceeded a predetermined limit.
 42. Themethod of claim 37, further comprising utilizing a filter to preventcollected fluid from flowing past the filter.
 43. The method of claim42, wherein the filter comprises a hydrophobic filter.
 44. The method ofclaim 37, wherein an overflow mechanism prevents fluid from flowing outof the cover.
 45. The method of claim 37, wherein the wound cover isflexible.
 46. The method of claim 37, wherein the membrane permits woundexudate to flow in a direction away from the wound, but does not permitwound exudate to flow in the opposite direction.